As road traffic has increased, the effects of increasing traffic congestion have had growing deleterious effects on business and government operations and on personal well-being. Accordingly, efforts have been made to combat the increasing traffic congestion in various ways, such as by obtaining information about current traffic conditions and providing the information to individuals and organizations. Such current traffic condition information may be provided to interested parties in various ways (e.g., via radio broadcasts, an Internet Web site that displays a map of a geographical area with color-coded information about current traffic congestion on some major roads in the geographical area, information sent to cellular telephones and other portable consumer devices, etc.).
One source for obtaining information about current traffic conditions includes observations manually supplied by humans (e.g., traffic helicopters that provide general information about traffic flow and accidents, reports called in by drivers via cellphones, etc.), while another source in some larger metropolitan areas is networks of traffic sensors capable of measuring traffic flow for various roads in the area (e.g., via sensors embedded in the road pavement). Unfortunately, various problems exist with respect to such information, as well as to information provided by other similar sources. For example, many roads do not have road sensors (e.g., geographic areas that do not have networks of road sensors and/or arterial roads that are not sufficiently large to have road sensors as part of a nearby network), and even roads that have road sensors may often not provide accurate data (e.g., sensors that are broken and do not provide any data or provide inaccurate data). In addition, while observations that are manually supplied by human may provide some value in limited situations, such information is typically limited to only a few areas at a time and typically lacks sufficient detail to be of significant use.